Wireless IC tag communication system has become widely used for physical distribution, parts management, and inventory management in recent years. In the wireless IC tag communication system, management is realized with a wireless IC tag (RFID tag), which is attached to an article or the like to be managed and in which information such as an identification code of the article or the like to be managed is written, and a reader/writer (interrogator) which reads out the information from the wireless IC tag. A manner to deal with errors caused by distortion generated in a communication channel is not specifically set down in standard of the wireless IC tag itself. Hence, conventionally, data in the wireless IC tags are processed through independent techniques for error control (See Patent Document 1, for example).
FIG. 9 is a diagram illustrating an allocation of memory regions in the wireless IC tag of the above-described system. In the above-described system, an error correcting code is applied to data before the data is written into the wireless IC tag as shown in FIG. 9. In communication between the reader/writer and the wireless IC tag, all of 128 bits shown in FIG. 9 are always employed, and the communication is made only with a reader/writer that has an error correcting function.    Patent Document 1: Japanese Patent Application Laid-Open No. 2004-29984